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91.
在28 nm低功耗工艺平台开发过程中,对1.26 V测试条件下出现的SRAM双比特失效问题进行了电性能失效模式分析及物性平面和物性断面分析.指出失效比特右侧位线接触孔底部空洞为SRAM制程上的缺陷所导致.并通过元素成分分析确定接触孔底部钨(W)的缺失,接触孔底部外围粘结阻挡层的氮化钛(TiN)填充完整.结合SRAM写操作的原理从电阻分压的机理上解释了较高压下双比特失效,1.05 V常压下单比特不稳定失效,0.84 V低电压下失效比特却通过测试的原因.1.26 V电压下容易发生的双比特失效是一种很特殊的SRAM失效,其分析过程及结论在集成电路制造行业尤其是对先进工艺制程研发过程具有较好的参考价值. 相似文献
92.
Hsin‐Te Lue Ming‐Gang Wen Hsu‐Yung Cheng Kuo‐Chin Fan Chih‐Wei Lin Chih‐Chang Yu 《ETRI Journal》2010,32(5):729-739
Due to the rapid development of mobile devices equipped with cameras, instant translation of any text seen in any context is possible. Mobile devices can serve as a translation tool by recognizing the texts presented in the captured scenes. Images captured by cameras will embed more external or unwanted effects which need not to be considered in traditional optical character recognition (OCR). In this paper, we segment a text image captured by mobile devices into individual single characters to facilitate OCR kernel processing. Before proceeding with character segmentation, text detection and text line construction need to be performed in advance. A novel character segmentation method which integrates touched character filters is employed on text images captured by cameras. In addition, periphery features are extracted from the segmented images of touched characters and fed as inputs to support vector machines to calculate the confident values. In our experiment, the accuracy rate of the proposed character segmentation system is 94.90%, which demonstrates the effectiveness of the proposed method. 相似文献
93.
Chung J. Kuo Wen J. Huang Tsang G. Lin 《Journal of Visual Communication and Image Representation》1999,10(4):307
Fractal image coding is an effective method to eliminate the image redundancy through piecewise self-transformability. The fractal code consists of a set of contractive affine transforms. To improve the performance when a range block experiences large error, we usually partition the range block into square or nonsquare subrange blocks for two- or multilevel fractal coding. In this paper, we find an inherent property of fractal coding that can be used to decide the edge orientation of a range block. Then this property is used for shape-adaptive fractal coding (SAFC). In SAFC, the top-level range block is partitioned into square or nonsquare (rectangle or triangle) subrange blocks for multilevel fractal encoding. Here, the maximum size of the range block can be the same as that of the whole image size while the minimum size is 4×4. In SAFC, no additional computations are required to obtain the edge orientation of a range block. Instead, we propose an edge-orientation detector, where the edge orientation of a range block is obtained during the fractal encoding process. According to our simulation results, SAFC can reduce the bit rate requirement of the conventional fractal coding scheme. 相似文献
94.
PCI总线是先进的高性能32/64位局部总线,是应用最广泛的微机总线标准之一。讨论了以CH365作为接口芯片的PCI总线接口卡的设计方法,并给出了一个ISA总线接口卡快速改造为PCI总线接口卡的实例。在设计中使用了CH365芯片特有的本地硬件地址请求功能及双口RAM读写的仲裁技术。设计的PCI接口板实现了预定的功能,具有较强的实用性和较高的市场推广价值。 相似文献
95.
96.
Shih-Cheng Yang Hsien-Chin Chin Feng-Tso Chien Yi-Jen Chan Kuo J.-M. 《Electron Device Letters, IEEE》2001,22(4):170-172
BCl3+CHF3 gas mixtures for the reactive ion etching process were applied to the gate-recess for fabricating (Al0.3Ga0.7)0.5In0.5P quaternary heterostructure double doped-channel FET's (D-DCFET), where a high uniformity of Vth was achieved. With the merits of this wide bandgap (Al0.3Ga0.7)0.5In0.5P layer, microwave power performance of this heterostructure D-DCFET demonstrates a compatible performance for devices fabricated on AlGaAs/InGaAs heterostructures 相似文献
97.
98.
Huang G.S. Lu T.C. Kuo H.C. Wang S.C. Hou-Guang Chen 《Photonics Technology Letters, IEEE》2007,19(13):999-1001
We report the fabrication of microcavity light-emitting diodes (MCLEDs) with high reflectivity and crack-free AlN-GaN distributed Bragg reflector (DBR). The 5lambda microcavity structure consists of an n-type GaN, ten pairs InGaN-GaN multiple quantum wells and p-type GaN sandwiched between the hybrid cavity mode of an AlN-GaN and a Ta2O5-SiO2 DBR. The AlN-GaN DBR has 29 periods with insertion of six AlN-GaN superlattice layers showing a crack-free surface morphology and a high peak reflectivity of 99.4% with a stopband of 21 nm. The output power of MCLED is about 11 W at an injection current of 7 mA. The electroluminescence has a polarization property with a degree of polarization of about 51%. 相似文献
99.
采空区遗煤自燃火灾是影响煤炭生产安全的主要灾害之一。基于Fluent数值模拟技术,构建采空区三维物理模型,模拟研究了采空区流场立体分布规律,并以O2体积分数为判别指标划分了采空区遗煤自燃危险区域;通过分析采空区遗煤空间分布规律及不同惰性气体的惰化特性,提出了综放工作面采空区复合惰化技术,即高位压注CO2和低位压注N2,并与单一气体惰化技术进行了对比研究。结果表明:复合惰化技术相较于单一气体惰化技术有着更好的防灭火效果;在工程应用中,各监测点CO体积分数在短时间内均降低到2.4×10-5以下,压注惰气期间防灭火效果良好。 相似文献
100.
The Industry Council for Electronic Equipment Recycling (ICER) has published estimates of waste generation based on both assumptions and analysis regarding the relationship between the market sales of Electrical and Electronic Equipment (EEE) in a given year and the expected lifetime of products as well as by employing market saturation factors. Waste EEE (WEEE) has an adverse impact on the environment. Therefore, it is important to reduce the quantity of WEEE through recycling. While attempting to improve the recycling rate of WEEE by enhancing the disassembly processes, two issues must be considered simultaneously—economy and safety. In this paper, a Petri Net (PN) based analysis approach is proposed to deal with the disassembly and recycling problems in End-Of-Life (EOL) WEEE. By using the PN analysis, the optimal tradeoff between the cost and environmental effectiveness of the disassembly processes is determined. A case study is used to illustrate the proposed analysis method. 相似文献